14-23416185-A-T

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 5P and 2B. PM1PM5PP2BP4_Moderate

The NM_000257.4(MYH7):​c.4772T>A​(p.Leu1591Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000353 in 1,613,934 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/23 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L1591P) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000036 ( 0 hom. )

Consequence

MYH7
NM_000257.4 missense

Scores

3
16

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:7

Conservation

PhyloP100: 1.37

Publications

8 publications found
Variant links:
Genes affected
MYH7 (HGNC:7577): (myosin heavy chain 7) Muscle myosin is a hexameric protein containing 2 heavy chain subunits, 2 alkali light chain subunits, and 2 regulatory light chain subunits. This gene encodes the beta (or slow) heavy chain subunit of cardiac myosin. It is expressed predominantly in normal human ventricle. It is also expressed in skeletal muscle tissues rich in slow-twitch type I muscle fibers. Changes in the relative abundance of this protein and the alpha (or fast) heavy subunit of cardiac myosin correlate with the contractile velocity of cardiac muscle. Its expression is also altered during thyroid hormone depletion and hemodynamic overloading. Mutations in this gene are associated with familial hypertrophic cardiomyopathy, myosin storage myopathy, dilated cardiomyopathy, and Laing distal myopathy. [provided by RefSeq, May 2022]
MHRT (HGNC:51291): (myosin heavy chain associated RNA transcript) This gene encodes a spliced long non-coding RNA that may act as a cardioprotective agent in the heart. Based on a study of a similar gene in mouse, the encoded transcript may regulate chromatin remodeling by acting as a decoy to the BRG1 chromatin repressor complex thus preventing it from binding to its genomic targets. Blocking the actions of BRG1 could be crucial in protecting the heart from pathological hypertrophy. [provided by RefSeq, Dec 2014]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM1
In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 16 uncertain in NM_000257.4
PM5
Other missense variant is known to change same aminoacid residue: Variant chr14-23416185-A-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 190406.
PP2
Missense variant in the MYH7 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 341 curated pathogenic missense variants (we use a threshold of 10). The gene has 16 curated benign missense variants. Gene score misZ: 3.9329 (above the threshold of 3.09). Trascript score misZ: 6.7889 (above the threshold of 3.09). GenCC associations: The gene is linked to myopathy, myosin storage, autosomal recessive, MYH7-related skeletal myopathy, congenital myopathy 7A, myosin storage, autosomal dominant, Ebstein anomaly, hyaline body myopathy, left ventricular noncompaction, hypertrophic cardiomyopathy 1, dilated cardiomyopathy 1S, dilated cardiomyopathy, congenital heart disease, familial isolated dilated cardiomyopathy, myopathy, myosin storage, autosomal dominant, arrhythmogenic right ventricular cardiomyopathy, hypertrophic cardiomyopathy.
BP4
Computational evidence support a benign effect (MetaRNN=0.11719307).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MYH7NM_000257.4 linkc.4772T>A p.Leu1591Gln missense_variant Exon 34 of 40 ENST00000355349.4 NP_000248.2
MYH7NM_001407004.1 linkc.4772T>A p.Leu1591Gln missense_variant Exon 33 of 39 NP_001393933.1
MHRTNR_126491.1 linkn.446A>T non_coding_transcript_exon_variant Exon 3 of 6

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MYH7ENST00000355349.4 linkc.4772T>A p.Leu1591Gln missense_variant Exon 34 of 40 1 NM_000257.4 ENSP00000347507.3
MYH7ENST00000713768.1 linkc.4772T>A p.Leu1591Gln missense_variant Exon 34 of 41 ENSP00000519070.1
MYH7ENST00000713769.1 linkc.4772T>A p.Leu1591Gln missense_variant Exon 33 of 39 ENSP00000519071.1

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
152088
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000398
AC:
10
AN:
251476
AF XY:
0.0000368
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000462
Gnomad NFE exome
AF:
0.0000527
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000356
AC:
52
AN:
1461846
Hom.:
0
Cov.:
34
AF XY:
0.0000344
AC XY:
25
AN XY:
727220
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000597
AC:
2
AN:
33480
American (AMR)
AF:
0.0000671
AC:
3
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.0000464
AC:
4
AN:
86256
European-Finnish (FIN)
AF:
0.0000749
AC:
4
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5750
European-Non Finnish (NFE)
AF:
0.0000279
AC:
31
AN:
1111984
Other (OTH)
AF:
0.000116
AC:
7
AN:
60396
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00000000000307443), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.396
Heterozygous variant carriers
0
3
6
10
13
16
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000329
AC:
5
AN:
152088
Hom.:
0
Cov.:
32
AF XY:
0.0000404
AC XY:
3
AN XY:
74280
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41406
American (AMR)
AF:
0.0000655
AC:
1
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5166
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10606
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.415
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000113
Hom.:
0
ExAC
AF:
0.0000576
AC:
7

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:7
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Cardiomyopathy Uncertain:3
Feb 06, 2024
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces leucine with glutamine at codon 1591 of the MYH7 protein. Computational prediction tools indicate that this variant has a neutral impact on protein structure and function. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in one individual affected with sudden cardiac death and myocarditis (PMID: 25447171). This individual and six relatives diagnosed with arrhythmogenic cardiomyopathy all carried a pathogenic truncation variant in the PKP2 gene that could explain the observed phenotype in this family (PMID: 31156706). This variant has been identified in 10/251476 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance.

Jan 11, 2024
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces leucine with glutamine at codon 1591 of the MYH7 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with sudden cardiac death and myocarditis (PMID 25447171). This individual and six relatives diagnosed with arrhythmogenic cardiomyopathy all carried a pathogenic truncation variant in the PKP2 gene that could explain the observed phenotype in this family (PMID: 31156706). This variant has been identified in 10/251476 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance.

Dec 21, 2020
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Congenital myopathy with fiber type disproportion;C1834481:Dilated cardiomyopathy 1S;C1842160:Myosin storage myopathy;C1850709:Myopathy, myosin storage, autosomal recessive;C3495498:Hypertrophic cardiomyopathy 1;C4552004:MYH7-related skeletal myopathy Uncertain:1
Sep 01, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

not provided Uncertain:1
Mar 07, 2022
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Hypertrophic cardiomyopathy Uncertain:1
Dec 23, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces leucine, which is neutral and non-polar, with glutamine, which is neutral and polar, at codon 1591 of the MYH7 protein (p.Leu1591Gln). This variant is present in population databases (rs730880808, gnomAD 0.007%). This missense change has been observed in individual(s) with Laing distal myopathy (PMID: 22918376). ClinVar contains an entry for this variant (Variation ID: 181265). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt MYH7 protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance.

Cardiovascular phenotype Uncertain:1
Dec 03, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.L1591Q variant (also known as c.4772T>A), located in coding exon 32 of the MYH7 gene, results from a T to A substitution at nucleotide position 4772. The leucine at codon 1591 is replaced by glutamine, an amino acid with dissimilar properties. This alteration has been reported in at least two cases of sudden cardiac death and has been seen in at least one hypertrophic cardiomyopathy (HCM) cohort (Campuzano O et al. Front Genet, 2019 May; Yamaguchi-Kabata Y et al. J Hum Genet, 2018 Feb;63:213-230; 10:450; Homburger JR et al. Proc Natl Acad Sci U S A, 2016 06;113:6701-6; Campuzano O et al. J. Am. Coll. Cardiol., 2015 Dec;66:2913-2914; Campuzano O et al. Forensic Sci Int, 2014 12;245:30-7). This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear.

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
CardioboostCm
Benign
0.056
BayesDel_addAF
Benign
-0.23
T
BayesDel_noAF
Benign
-0.39
CADD
Benign
16
DANN
Benign
0.93
DEOGEN2
Uncertain
0.44
T
Eigen
Benign
-0.68
Eigen_PC
Benign
-0.38
FATHMM_MKL
Benign
0.56
D
LIST_S2
Benign
0.61
T
M_CAP
Uncertain
0.15
D
MetaRNN
Benign
0.12
T
MetaSVM
Benign
-0.88
T
MutationAssessor
Benign
-1.8
N
PhyloP100
1.4
PrimateAI
Uncertain
0.59
T
PROVEAN
Benign
1.9
N
REVEL
Benign
0.25
Sift
Benign
1.0
T
Sift4G
Benign
0.73
T
Vest4
0.23
ClinPred
0.030
T
GERP RS
4.5
Varity_R
0.22
gMVP
0.52
Mutation Taster
=26/74
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs730880808; hg19: chr14-23885394; COSMIC: COSV62524609; COSMIC: COSV62524609; API